A major technical issue in the wine industry is the unpredictable incidences of problems that occur once wine has been bottled due to the properties of the closures used.
Traditional cork closures have problems with taint, caused in a major part by Trichloroanisoles (TCA) known more commonly as corked taint or causing “corked wine”. It has been estimated that the wine in up to 10% of all bottles of wine produced worldwide may be affected in this manner. A more recently recognised problem with using cork as a closure is the physical nature of cork having variability to the permeation of oxygen which can lead to inconsistent and uneven development of the bottled wine. Leakage has always been as issue associated with cork caused by a fault line or lines or porosity in the cork.
The continued and increasing dissatisfaction amongst wine makers with the performance of natural cork as a closure has led to some use of synthetic material and varying forms of approach such as the screw top “STELVIN™” cap. There have been issues of taint and other performance issues from synthetic materials and the screw type closures and there is limited experience and testing of the performance of these materials. There is also considerable market resistance to the use of synthetic materials.
In EP 1549556 there is disclosure of a closure which uses surface tension to effect a seal. The seal takes place between two very flat abutting surfaces. In one embodiment of EP 1549556 the top of a glass wine bottle is polished to a flatness of 2 to 3 wavelengths of light and a glass disk of similar flatness is put on top of the bottle with pressure applied to create a seal. Although in a production environment there are technologies to produce very flat surfaces in materials such as glass and ceramics it is has proven very difficult to consistently achieve a flat surface that doesn't include imperfections, i.e. cavities, scratches etc. The presence of surface imperfections that are particularly prominent in certain production environments results in the seal lacking the quality desired when used as a closure for wine bottles.
It is these issues that have brought about the present invention.